Deoxidizer



1% Drawing.

atentecl Sept. l,

stare isnssa ear s-pr K FEEEQE AYLI'EER AND 'W'ILLIABI C. VJILHAR-M,

H. 'WIAUDE, CLARENCE J. ROIDTJIAN, AND CHABLESASTYERfOF VIIIHHNSIBUER-G,

OF EDGEWOOD, PENNSYLVANIA, HSSIG-NORS TO WEST- ENG-HOUSE ELECTRIC & MANUFACTURING COMPANY, A COEPGBAPTION OF PEN N SYLVANIA DEOXIDIZER- This inven ion relates to means for removing oxygen from atmospheres containing the same, more especially to the removal of the oxyp n from the spaces above the oil in elect ical apparatus such as transformers, cuit breakers .oil s *itches and the like. in such electrical apparatus it is customb0 place the transformer body, or the r ..e, within a metal container or tank and to cover the same with a high grade insulating A space is left above the oil level to per it expansion thereof under normal operat: conditions, and there is usually provide means whereby communication is allowed to the outside air, in order that upon cx ansion contraction of the il, air may be forced out or drawn in, a phenomenon which is known as breathing.

Jpon an are forming in the oil, either accidentally or during the normal operation of the a paratus, combustible gases which mix with the air in the space above the oil, are produced, forming an explosive mixture. This mixture has, on different occasions, been ignited by arcs within the apparatus, causing explosions which damaged the same, and emlangered the lives of station attendants or worhnien. Furthermore, the oxygen in the air which is breathed by the transformer, gradually reacts with the oil, forming a sludge which is detrimental to the insulati properties thereof.

provide an inert atmosphere in the container. One of the means was to provide a material through which all the air necessary for the breathing of the transformer shall pass, the

'a i being capable of abso- 'ng the on from the air, thus rendering the above the oil inert and preventiation of explosive mixtures. invention relates to materials of this character, it being amongthe objects thereof to provide a material which shall be effective in removim oxygen from atmos A s containing the same, which shall not leteriorate and which shall be reactive under all the normal operating conditions of the apparatus.

Application filed. December 21, 1923. Serial N0.- 682,097.

substances capable of producing ions in solution, certain metals,1such as'copper, are capable of forming oxidation'products with the oxygen of the air. We have further found that theuse of equivalent proportions of the metal and electrolyte gives the best r sults. This is probably owing to the formation of a double salt of the two materials, which facilitates the oxidation reaction thereof.

The action may be'accelerated by the addition of finely divided catalytic material, such as activate-cl carbon and also by theuse of highly porous inert material ponwhich' the active ingredients are deposited. If desired, we may utilize a combination of the said materials in our mixtures.

It has been found that a mixture'of this character, although effective at ordinary temperatures, becomes .less effective at tr mely low temperatures (below '-15 and may cease to function ifsuchextreme temperatures are reached. To :preventthe loss of activityat the .low.temperatui'cs,:an electrolyte such as calcium chloride which is capable of depressing the freezing point of the material may be added, and is, in itself, capable of causing the metal to remain reactive.

The addition of an electrolyte to depress the freezingpoint, how-ever, is not essential when the apparatus is being operated at normal atmospheric temperatureaits addition only being requisite whenlthe apparatus is being operated at abnormal atmospheric temperatures. For example, when calcium chloride is added, the composition is stable and reactive at temperatures as low as .3'5' C. It will be understoodthat the addition of calcium chloride doesnot'formapart of the present invention, as compositions including its use are described andclaimed in copending application, Serial No. 682,098 to Ford et al. which .is also assigned to the lVestinghouse Electric -& .Manufacturing Company.

Per cent Copper- 44.6 Ammonium chloride 36.2 Kieselguhr 4L2 Calcium chloride (6H O) .3

Activated carbon Water lxl A method of preparation of the above mixture which has been found suitable, is as follows: Copper oxide scale is ground and then mixed with 10% of its weight of silica, preferably in the form of kieselguhr. The mixture is then reduced with a reducing gas, such as natural gas or other reducing gas such as hydrogen to give a mixture of finely divided copper and kiesel uhr. The material is sifted to obtain particles which pass through a ZOO-mesh sieve, and the remaining ingredients are added and mixed in an inert atmosphere of ni..rogen or carbon dioxide.

Our preferred mixture for normal operating conditions is the same as that given above with the exception that the calcium chloride is omitted. This would render the proportions substantially as follows:

Per cent Copper A16 Ammonium chloride 38.6 Kieselguhr 45.5 Activated carbon 4.6 Water 4:.7

Activated carbon may be substituted in whole or in part for the kieselguhr catalyzer or spacer material since one of the main purposes of the catalyzer is to act as a separator for preventing the chemically reactive mixture from packing, and for maintaining the reactive material in such condition that the gas may readily and completely combine therewith.

The reactive mixture may be packed in a container much the same as kieselguhr itself would be. l/Vhen gas is passed over the surface of the material and conducted therethrough, the total effect is that the gas r'e acts completely with the uppermost layers of the mixture, resulting in a sharply defined plane of demarcation that extends entirely across the container between the dis- -colored layer of exhausted material and the eensse maining ingredients are added and mixed in" an inert atmosphere.

This mixture is very effective for the pur pose specified, in that the material does not deteriorate on standing, since there is no undesirable reaction taking place between the ingredients thereof. It is not affected by the humidity of the air and by ordinary temperature changes, and is stable in to a temperature of about C.

Although we have described our iiwention setting for h specific embodiments thereof, various changes may be made in the composition and the manner of making the same, within the scope of our invention. For instance, instead of ammonium chloride, other an'nnonium such as the sulphate, fiuoride, or the like may be used. The inert material may be inorganic or organic, such as cork dust, sawdust, asbestos or other materials having the desired characteristics. The activated carbon may be omitted if de sired, but there are indications that both the inert material and the activated carbon are effective in increasing the efliciency of the reaction. The carbon may be in any of its well-known forms, such as carbon black, coke dust, activated charcoal, or deflocculated graphite. The proportions of the ingredients may be varied within wide ran es and still produce effective mixtures.

While copper has been specifically mentioned and is preferred as the oxidizable metal which may be utilized, it will be under stood that other oxidizable metals may be employed such as those disclosed copending application, Serial No. 682,075, assigned to the Westinghouse Electric & Manufacturing Company, which has matured into Patent No. 1552, 596, dated Dccem sier 13, 1927.

Ve claim as our invention:

1. A material for deoxidizing atmospheres comprising copper, a. ammonium salt, kieselguhr and water.

2. A material for deoxidizing atmospheres comprising copper, ammonium chloride, kieselguhr and water, the copper and ammonium chloride being in substantially equimolecular proportions.

3. A material for dcoxidizing atmospheres comprising an oxidizable metal, electrolyte and a catalyzer, said electrolyte being non-reactive with said metal in theabsence of oxygen.

4. A material. for deoxidizingatmospheres comprising an oxidizable metal, an electrolyte and carbon, said electrolyte being nonreactive with said metal in the. absence of oxygen.

5. A material for deoxidizingatmospheres comprising an oxidizable metal, an electrolyte that is non-reactive with said .metal in the absence of oxygen and activated carbon.

'6. A material for deoxidizing atmospheres comprising an oxidizableametal, a-nelectrolyte that is non-reactive with said metal in the absence of oxygen, a catalyzer and water.

7. A material for deox-idizing atmospheres comprising an oxidizable metal, an elect-rolyte that is non-reactive with said metal in the absence of oxygen, activated carbon and water.

8. A material for deoxidizin atmospheres comprising copper, a salt of ammonia, kieselguhr, activated carbon and water.

9. A material for deoxidizing gases capable of reacting with oxygen at normal atmospheric temperatures which comprises an oxidizable metal, an ammonium salt and water.

10. A material for deoxidizing gases capable of reacting with oxygen at normal atmospheric temperatures which comprises copper, an inert spacing material, an ammonium compound and water, said cop-per and alkali compound being in substantially equim lecular proportions.

11. A material for deoxidizing gases capable of reacting with oxygen at normal atmospheric temperatures which comprises a mixture of finely divided copper, a finely divided inert material and ammonium chloride.

12. A material for deoxidizing gases capable of reacting with oxygen at normal atmospheric temperatures comprising 40 to parts of a finely divided oxidizable metal, a substantially equimolecular proportion of an ammonium compound, approximately 4; parts of finely divided inert material and water.

13. A material for deoxidizing gases capable of reacting with oxygen at normal atmospheric temperatures comprising 40 to 60 parts of finely divided copper, a substantially equimolecular proportion of an ammonium compound, approximately 4 parts of finely divided inert material and approximately 5 parts of water.

14. A material for deoxidizing atmospheres comprising copper, an ammonium salt, kieselguhr, activated carbon and water, the copper and chloride being in substantially equimolecular proportions.

15. A material for deoxidizing atmospheres comprising copper, ammonium chloride, kieselguhr, activated carbon and water, the-copper and chloride being in substantially equnnolecular proportions and the ki-eselg-uhr and carbon being 1n minor proportions.

516. .A material which comprisesa anetal oxidizableat temperatures below ,C.

and an electrolyte that is non-reactive with said metal in the absence of oxygen, said chemically active toward each other inthe' presence of oxygen and toward atmospheres at normal. atmospheric temperatures, whereby oxidizing gases in said atmospheres .are reduced.

18. A material which comprises water,

metal oxidiza'ble at temperatures below 120 (landan electrolyte that is non-reactive toward said metal in the absence of oxygen, said metal and electrolyte being chemically active toward each otherin the presence of oxygenland toward. atmospheres at normal atmospheric temperatures, whereby oxidizinggases in said atmospheres are reduced.

19. A material which comprises .wa-ter, substantially equivalent proportions 01 a metal oxidizable at temperatures below 120 C. and an electrolyte .that is non-reactive toward said metal in the absence of oxygen, said metal and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in .said atmospheres are reduced.

20. A material which comprises aamctal oxidiZa-ble attemperatures below 120 C. and an ammonium salt, said metal and salt being chemically active 'towardeach other and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

21...,A materiahwhieh comprises substantially equivalent proportions-of a metal oxidizable at temperatures below 120 C. and an ammonium halide salt, saidmetal and salt being chemically active toward each other and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

22. Aniaterial which comprises water, a metal-oxidizable at temperatures-below 120 C. and an ammonium halide SillQqSfliCllflQlZ-fll and salt=being chemically active toward each other and'toward atmospheres at normal. atmospheric temperatures, whereby oxidizing gases in said atmospheresarereduced.

23. A material which comprises water, substantially equivalent proportions of a metal oxidizable at temperatures below 120 C. and an ammonium halide salt, said metal and salt being chemically active toward each other and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

4-. A material which comprises copper and an electrolyte that is non-reactive toward copper in the absence 01" oxygen, said copper and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

25. A material which comprises substantially equivalent proportions of copper and an electrolyte that is non-reactive toward copper in the absence of oxygen, said copper and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

26. A material which comprises water, copper and an electrolyte that is non-reactive toward copper in the absence of oxy gen, said copper and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

27. A material which comprises water, substantially equivalent proportions of copper and an electrolyte that is non-reactive toward copper in the absence of-oxygen, said copper and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

28. A material which comprises finely divided copper and an electrolyte that is non-reactive toward copper in the absence of oxygen, said copper and electrolyte being chemically active toward each other and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

29. A material which comprises water, finely divided copper and an electrolyte that is non-reactive toward copper in the absence of oxygen, said copper and electrolyte being chemically active toward each other in the presence of oxygen and toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

30. A material which comprises water, copper and ammonium chloride, said material being chemically active toward atmospheres at normal atmospheric temperatures,

aises whereby oxidizing gases in said atmospheres are reduced.

31. A materlal which comprises water,

copper and ammonium chloride, said copper.

tures, whereby oxidizing gases in said at-.

mospheres are reduced.

32. A material which comprises water, finely divided copper and ammonium chloride, said material being chemically active toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

33. A material which comprises finely divided copper, ammonium chloride and water distributed throughout a mass of inactive spacing material, said material being chemically active toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

34. A material which comprises finely divided copper, ammonium chloride and water distributed throughout amass of inactive spacing material, said copper and am monium chloride being in substantially equivalent proportions, said material being chemically active toward atmospheres at normal atmospheric temperatures, whereby oxidizing gases in said atmospheres are reduced.

In testimony whereof, we have hereunto subscribed our names this 17th day of December, 1923.

AYLMER H. MAUDE. CLARENCE J. RODMAN. CHARLES A. STYER. WILLIAM C. lVILl-IARM. 

